Comment by eastbayjake

It's such a broad question... are you a consumer or a merchant? Are you doing a card-present payment (eg swiping at a store POS) or a card-not-present payment (eg entering your credit card number on an ecommerce site)? Are you buying/selling a high-risk item? How much do you care about privacy? How much do you care about rewards (if you're a consumer) or processing fees (if you're a merchant)?